Hello Dean,
Pushed. I decided not to go with the "joke" randu64() function, but instead used getrand() directly. This at least removes any *direct* use of doubles in permute() (though of course they're still used indirectly), and means that if getrand() is improved in the future, permute() will benefit too.
Good idea, at least it is hidden and in one place. Thanks for the push! -- Fabien.
